High-pressure pumps for the injection of fuel into a combustion engine, such as high-pressure gasoline pumps, are positioned on one of the camshafts of the combustion engine. In conjunction with a spring, cams specially configured for the high-pressure pump ensure that a piston travel in the high-pressure pump induces a delivery of the fuel into the fuel rail via a non-return valve. The particular fuel quantity per stroke is determined by an electrical actuation of a quantity-control valve (QCV) in the high-pressure pump.
Conventionally, the actuation of the quantity-control valve and the calculation of parameters that are required in this context, such as the pressure acquisition of the rail pressure, the high-pressure control and the actuation angle of the quantity-control valve, are carried out in a time frame of 10 ms, for example. At low engine speeds, this time frame is narrow enough to execute control operations and calculations in a sufficiently precise manner. At high engine speeds, depending on the number of cams, the cam frequency becomes higher than the time frame frequency, and it is no longer possible to incorporate the most recent parameters in the control calculation for each delivery of fuel. In the event that the high-pressure fuel pump is driven by a rapidly adjusted camshaft, the execution of control calculations with old parameters leads to an error. This error is unable to be compensated for in a calculation within the time frame inasmuch as the calculation takes place in an asynchronous manner to the control operation of the high-pressure pump. The error caused by the rapid camshaft adjustment is particularly noticeable at low rotational speeds of the combustion engine. The maximum total error lies in the medium rotational speed range. It manifests itself by pressure oscillations in the fuel rail.